Effects of dietary iron supplementation on reproductive performance of sows and growth performance of piglets.

This experiment aimed to investigate the effects of dietary iron supplementation from different sources on the reproductive performance of sows and the growth performance of piglets. A total of 87 sows with similar farrowing time were blocked by body weight at day 85 of gestation, and assigned to one of three dietary treatments (n = 29 per treatment): basal diet, basal diet supplemented with 0.2% ferrous sulfate (FeSO4), and basal diet supplemented with 0.2% iron sucrose, respectively, with 30% iron in both FeSO4 and iron sucrose. Compared with the control (CON) group, iron sucrose supplementation reduced the rate of stillbirth and invalid of neonatal piglets (P < 0.05), and the number of mummified fetuses was 0. Moreover, it also improved the coat color of newborn piglets (P < 0.05). At the same time, the iron sucrose could also achieve 100% estrus rate of sows. Compared with the CON group, FeSO4 and iron sucrose supplementation increased the serum iron content of weaned piglets (P < 0.05). In addition, iron sucrose increased serum transferrin level of weaned piglets (P < 0.05) and the survival rate of piglets (P < 0.05). In general, both iron sucrose and FeSO4 could affect the blood iron status of weaned piglets, while iron sucrose also had a positive effect on the healthy development of newborn and weaned piglets, and was more effective than FeSO4 in improving the performance of sows and piglets.

Sows need more iron to meet the requirements for their and offspring's growth during pregnancy and lactation. Exogenous iron supplementation may improve the reproductive performance of sows and the growth performance of piglets, but different sources of iron have different effects. This study facilitates the understanding of the effects of iron sucrose and ferrous sulfate on the reproductive performance of sows and the growth performance of piglets.

Review: Improving the performance of neonatal piglets.

Newborn piglets have a high incidence of preweaning mortality that is not only associated with low birth weights but also with the presence of intra-uterine growth-restricted (IUGR) piglets. Such IUGR piglets are commonly seen in litters from hyperprolific sows as a result of insufficient placental transfer of nutrients. Nutritional strategies can be used prior to and during gestation to enhance foetal development and can also be implemented in the transition period to reduce the duration of farrowing and increase colostrum yield. Recent findings showed that the energy status of sows at the onset of farrowing is crucial to diminish stillbirth rate. Newborn piglets often fail to consume enough colostrum to promote thermostability and subsequent growth, and this is particularly problematic in very large litters when there are fewer available teats than the number of suckling piglets. One injection of 75 IU of oxytocin approximately 14 h after farrowing can prolong the colostral phase, hence increasing the supply of immunoglobulins to piglets. Nevertheless, assistance must be provided to piglets after birth in order to increase their chance of survival. Various approaches can be used, such as: (1) optimising the farrowing environment, (2) supervising farrowing and assisting newborn piglets, (3) using cross-fostering techniques, (4) providing nurse sows, and 5) providing artificial milk. Although research advances have been made in developing feeding and management strategies for sows that increase performance of their newborn piglets, much work still remains to be done to ensure that maximal outcomes are achieved.

Distribution difference of colostrum-derived B and T cells subsets in gilts and sows.

Piglets are highly vulnerable to infections, but colostrum provides them with some protection. The function of colostrum components is unknown, as is if the amount and subsets of leukocytes in colostrum differ between gilts and sows. This study serially characterized leukocyte populations in colostrum for differential leukocyte counts. Differences in humoral and cellular composition of colostrum between 40 gilts and 40 sows (parities orders 3-4) from a commercial herd were examined. Flow cytometry is a useful tool to identify and quantify leukocyte subsets in sow colostrum. Overall, there were no (p ≥ 0.05) parity differences in total macrophages, granulocytes, and T and B cells. However, the sows' colostrum presented significantly higher (p ≤ 0.05) T lymphocyte subsets than gilts, such as central memory CD4+T cells, effector memory CD4+T cells, and central memory CD8+T cells. Among B-lymphocytes, percentages of SWC7+CD5+ cells were significantly higher in sow colostrum than in that of gilts. As expected, IgG concentrations were significantly higher in sows than in gilts. Colostrum from sows had significantly greater mitogenic activity than colostrum from gilts and this fact can be associated with the potential to accelerate the maturation of a newborn's gastrointestinal tract. Our findings suggest that parity order may be one among other factors influencing the cell population and, consequently, the immune adaptive response in piglets that induces neutralizing antibodies and cellular immune responses to antigens.

Meta-analysis identifies the effect of dietary multi-enzyme supplementation on gut health of pigs.

Gut health though is not well defined the role of gastrointestinal tract is vital if an animal must perform well. Apart from digestion, secretion, and absorption gut is harbored with consortium of microbiota which plays a key role in one's health. Enzymes, one of the alternatives for antibiotics with beneficial effects on digestion and consistency of food and its effect on gut health. The effect of enzyme supplementation on gut health is not well established and the objective of this meta-analysis is to investigate if the enzyme supplement has influence on gut. This meta-analysis includes 1221 experiments which has single enzyme studies and or studies with multiple enzyme complexes but not challenged. The ratio of Lactobacillus and E. coli is related to ADFI which showed comparatively lower negative correlation coefficient, with - 0.052 and - 0.035, respectively, whose I2 values are below 25%, showing that these studies show a significantly lower level of heterogeneity. Correlation between villus height, crypt depth, their ratio and fatty acid is also assessed, and it showed that when the animal is supplemented with two enzyme complexes resulted in positive gut health rather than the single or more than two enzymes.

Effects of apple polyphenols on myofiber-type transformation in longissimus dorsi muscle of finishing pigs.

This study aimed to investigate effects of apple polyphenols (APPs) on myofiber-type transformation in longissimus dorsi muscle of finishing pigs and its mechanism. In this study, 36 healthy castrated Duroc × Landrace × Yorkshire pigs with an average body weight of 71.25 ± 2.40 kg were randomly divided into three treatment groups (control, 0.04% APPs, 0.08% APPs). The experiment lasted for 49 days. Results showed that dietary APP supplementation increased the protein expression of MyHC I and the activities of succinic dehydrogenase and malate dehydrogenase, as well as decreased the protein expression of MyHC IIb and the activity of lactate dehydrogenase, suggesting that APPs promoted muscle fiber-type transformation from fast-twitch to slow-twitch in finishing pigs. We also showed that dietary 0.08% APP supplementation increased the expressions of mitochondrial biogenesis and function-related proteins PGC-1α, Sirt1 and Cytc. In addition, dietary supplementation with 0.08% APPs increased the activities of T-SOD, GSH-PX and CAT and decreased the MDA content. Together, we provided the first evidence that APP promotes muscle fiber-type transformation from fast-twitch to slow-twitch in finishing pigs, which may be achieved by improving the mitochondrial biogenesis and function and increasing the antioxidant capacity of skeletal muscle.

Effects of dietary resveratrol supplementation on immunity, antioxidative capacity and intestinal barrier function in weaning piglets.

The aim of this study was to investigate effects of dietary supplementation of resveratrol on immunity, antioxidative capacity, intestinal barrier function in weaning piglets. Here, fifty-four 28-day-old Duroc × Landrace × Yorkshire weaning piglets were randomly divided into three dietary treatments and fed with a basal diet or a basal diet supplemented with 150 and 300 mg/kg resveratrol, respectively, for 42 days. The results indicated that resveratrol increased serum immunoglobulin G content. In serum, resveratrol increased glutathione peroxidase enzyme activity and decreased malondialdehyde (MDA) content. In liver, resveratrol not only increased T-AOC and total superoxide dismutase enzyme activities but also decreased MDA content. Meanwhile, the results showed that resveratrol had significantly increased the jejunum villus height and villus height/crypt depth, and decreased the crypt depth in jejunum. Furthermore, the mRNA expressions of IL-10 and ZO-1 were significantly increased in jejunal mucosa. However, there was no significant difference in the mRNA expressions of TNF-α, IL-1ß, IL-6, Occludin and Claudin1 between the treatment groups and the control group. Taken together, these results indicated that dietary supplementation of resveratrol could increase antioxidant activity, promote the integrity of intestinal barrier and increase the production of anti-inflammatory cytokines in weaning piglets.

Impact of arginine supplementation on serum prolactin and mRNA abundance of amino acid transporter genes in mammary tissue of lactating sows.

This study was conducted to test the hypothesis that supplemental dietary Arg to late-pregnant and lactating sows increases serum prolactin concentrations and mRNA abundance of SLC7A1, SLC7A2, and SLC6A14 in mammary parenchymal tissue. From day 108 of gestation and until day 21 of lactation, sows were fed a diet either supplemented with 0.10 g of l-Arg/kg body weight (BW) per day (n = 10, ARG) or 0.34 g of l-Glu/kg BW per day (n = 10, control). Litters were standardized to 10 piglets on day 1 of lactation and piglets were weighed on days 1, 7, 14, and 21 of lactation. Sow BW was recorded on day 108 of gestation and days 1, 10, and 21 of lactation. Lactation sow feed intake was recorded daily. Mammary parenchymal tissue was biopsied on day 5 of lactation to measure mRNA abundance SLC7A1, SLC7A2, and SLC6A14. On days 4 and 18 of lactation, blood samples were collected from sows at 2, 4, and 6 hr postfeeding to measure serum prolactin concentrations. Milk samples were collected on days 4, 10, and 18 of lactation to measure fat, lactose, urea N, and true protein concentrations. Sow BW, backfat, and feed intake over all sampling days did not differ between treatments. Piglet BW on d 1 tended to be greater for the ARG treatment than the control treatment (P = 0.12). Sow milk yield and composition (fat, protein, lactose, and urea N) and mammary mRNA abundance of candidate genes did not differ between the ARG and the control group. Compared to controls, serum prolactin concentrations tended to be greater (P = 0.08) in ARG sows on day 4 of lactation, and did not differ on day 18. Current findings show a potential beneficial effect of dietary supplementation with Arg to late-pregnant multiparous sows on BW of their piglets on day 1. Dietary Arg supplementation at a rate of 0.10 g/kg BW during late pregnancy and lactation tended to increase serum prolactin concentrations with no increase in mammary transcript abundance of SLC7A1, SLC7A2, and SLC6A14 in early lactation.

Soybean meal allergenic protein degradation and gut health of piglets fed protease-supplemented diets.

Two experiments were conducted to determine the effects of protease supplementation on degradation of soybean meal (SBM) allergenic proteins (glycinin and ß-conglycinin) and gut health of weaned pigs fed soybean meal-based diets. In experiment 1, 2 SBM samples from 2 different sources were subjected to porcine in vitro gastric degradation to determine the effects of protease (at 15,000 U/kg of feedstuff) on degradation of the soybean allergenic proteins. In experiment 2, 48 weaned pigs (body weight = 6.66 kg) were obtained in 2 batches of 24 pigs each. Pigs were individually housed in metabolic crates and fed 4 diets (12 pigs/diet). The diets were corn-based diet with SBM 1 or SBM 2 without or with protease at 15,000 U/kg of diet in 2 × 2 factorial arrangement. Diets were fed for 10 d and pigs were sacrificed on day 10 for measurement of small intestinal histomorphology, permeability of small intestine mounted in Ussing chambers, and serum concentration of pro-inflammatory cytokines. Two SBM sources (SBM 1 and SBM 2) contained 46.9% or 47.7% CP, 14.0% or 14.6% glycinin, and 9.90% or 10.3% ß-conglycinin, respectively. Protease and SBM source did not interact on any of the response criteria measured in the current study. Protease supplementation tended to increase (P = 0.069) the in vitro gastric degradation of glycinin. Protease supplementation tended to reduce (P = 0.099) fluorescein isothiocyanate dextran 4,000 Da (which is a marker probe for intestinal permeability) flow in jejunum, and reduced (P = 0.037) serum TNF-α concentration. Protease did not affect small intestinal histomorphology. In conclusion, protease tended to increase gastric degradation of glycinin and reduce gut permeability, and serum concentration of pro-inflammatory cytokines, indicating that the protease used in the current study can be added to SBM-based diets for weanling pigs to improve gut health.

Growth performance, nutrient digestibility, and fecal microbial composition of weaned pigs fed multi-enzyme supplemented diets.

A study determined the effects of supplementing corn-based diets for weaned pigs with multi-enzymes on growth performance, apparent total tract digestibility (ATTD) of nutrients, fecal score, and fecal microbial composition. A total of 132 pigs (initial body weight = 7.23 kg) that had been weaned at 21 d of age and fed a drug-free nursery diet for 7 d were housed in 33 pens of 4 barrows or gilts, blocked by body weight and gender, and fed 3 experimental diets at 11 pens per diet. The diets were corn-based diet without or with multi-enzyme A or B. Multi-enzyme A supplied 4,000 U of xylanase, 150 U of ß-glucanase, 3,500 U of protease, and 1,500 U of amylase per kilogram of diet. Multi-enzyme B was the same as multi-enzyme A except that it supplied amylase at 150 U/kg, and that its source of amylase was different from that of multi-enzyme A. All diets contained phytase at 1,000 U/kg. The diets were fed for 35 d in 2 phases; phase 1 for the first 14 d and phase 2 for the last 21 d of the trial. Fecal score was determined daily during the first 7 d of the trial. Fecal samples were collected from rectum of 1 pig per pen on days 2, 7, 14, and 35 of the trial for determining bacterial composition. Also, fresh fecal samples were collected from each pen on days 41 and 42 to determine ATTD of nutrients. Multi-enzyme B increased (P < 0.05) average daily gain (ADG) for phases 1 and 2. For the overall study period, multi-enzyme B increased (P < 0.05) ADG from 262 to 313 g, and average daily feed intake (ADFI) from 419 to 504 g. Multi-enzyme A increased (P < 0.05) overall ADG from 262 to 290 g, but did not affect ADFI. Multi-enzyme A or B did not affect ATTD of gross energy, but increased (P < 0.05) the ATTD of ether extract from 30% to 36% or 37%, respectively. Multi-enzyme A did not affect fecal score; however, multi-enzyme B tended to decrease (P = 0.09) fecal score, implying that it tended to decrease diarrhea. Firmicutes were the most abundant phylum of fecal bacteria (its relative abundance ranged from 58% to 72%). Bacteroidetes and Actinobacteria were the 2nd and 3rd most abundant phyla of fecal bacteria. Neither multi-enzyme affected fecal bacterial composition. In conclusion, the addition of multi-enzyme A or B to phytase-supplemented corn-based diet for weaned pigs can improve their growth performance and fat digestibility. However, multi-enzyme B was more effective than multi-enzyme A in terms of improving the growth performance of weaned pigs fed corn-based diet.

Xylanase supplementation in corn-based swine diets: a review with emphasis on potential mechanisms of action.

Corn is a common energy source in pig diets globally; when financially warranted, industrial corn coproducts, such as corn distiller's dried grains with solubles (DDGS), are also employed. The energy provided by corn stems largely from starch, with some contribution from protein, fat, and non-starch polysaccharides (NSP). When corn DDGS are used in the diet, it will reduce starch within the diet; increase dietary protein, fat, and NSP levels; and alter the source profile of dietary energy. Arabinoxylans (AXs) comprise the majority of NSP in corn and its coproducts. One strategy to mitigate the antinutritive effects of NSP and improve its contribution to energy is by including carbohydrases within the diet. Xylanase is a carbohydrase that targets the ß-1,4-glycosidic bonds of AX, releasing a mixture of smaller polysaccharides, oligosaccharides, and pentoses that could potentially be used by the pig. Xylanase is consistently effective in poultry production and moderately consistent in wheat-based swine diets, but its efficacy in corn-based swine diets is quite variable. Xylanase has been shown to improve the digestibility of various components of swine-based diets, but this seldom translates into an improvement in growth performance. Indeed, a review of xylanase literature conducted herein suggests that xylanase improves the digestibility of dietary fiber at least 50% of the time in pigs fed corn-based diets, but only 33% and 26% of the time was there an increase in average daily gain or feed efficiency, respectively. Intriguingly, there has been an abundance of reports proposing xylanase alters intestinal barrier integrity, inflammatory responses, oxidative status, and other health markers in the pig. Notably, xylanase has shown to reduce mortality in both high and low health commercial herds. These inconsistencies in performance metrics, and unexpected health benefits, warrant a greater understanding of the in vivo mechanism(s) of action (MOA) of xylanase. While the MOA of xylanase has been postulated considerably in the literature and widely studied in in vitro settings, in wheat-based diets, and in poultry, there is a dearth of understanding of the in vivo MOA in pigs fed corn-based diets. The purpose of this review is to explore the role of xylanase in corn-based swine diets, discuss responses observed when supplemented in diets containing corn-based fiber, suggest potential MOA of xylanase, and identify critical research gaps.

Reduced phosphorus intake throughout gestation and lactation of sows is mitigated by transcriptional adaptations in kidney and intestine.

BACKGROUND: The environmental impact of pig farming need to be reduced, with phosphorus (P) being of particular interest. Specified dietary regimens and management systems contribute to meet environmental concerns and reduce economic constrains. However, pregnant and lactating sows represent vulnerable individuals, whose reproductive potential and metabolic health status relies on adequate supply of macro- and micronutrients. The aim of this study was to investigate, whether sows fed with a dietary P content that is below or above current recommendations are capable to maintain mineral homeostasis during the reproduction cycle and which endogenous mechanisms are retrieved therefore in kidney and jejunum. Nulliparous gilts were fed iso-energetic diets with recommended (M), reduced (L), or high (H) amounts of mineral P supplements throughout gestation and lactation periods. Blood metabolites and hormones referring to the P homeostasis were retrieved prior to term (110 days of gestation) and at weaning (28 days of lactation). Transcriptional responses in kidney cortex and jejunal mucosa were analyzed using RNA sequencing. RESULTS: The variable dietary P content neither led to an aberration on fertility traits such as total weaned piglets nor to an effect on the weight pattern throughout gestation and lactation. Serum parameters revealed a maintained P homeostasis as reflected by unaltered inorganic P and calcium levels in L and H fed groups. The serum calcitriol levels were increased in lactating L sows. The endocrine responses to the dietary challenge were reflected at the transcriptional level. L diets led to an increase in CYP27B1 expression in the kidney compared to the H group and to an altered gene expression associated with lipid metabolism in the kidney and immune response in the jejunum. CONCLUSIONS: Our results suggest that current P requirements for gestating and lactating sows are sufficient and over supplementation of mineral P is not required. Shifts in renal and jejunal expression patterns between L and H groups indicate an affected intermediate metabolism, which long-term relevance needs to be further clarified.

Replacing dietary antibiotics with 0.20% l-glutamine and synbiotics following weaning and transport in pigs.

Dietary antibiotic use has been limited in swine production due to concerns regarding antibiotic resistance. However, this may negatively impact the health, productivity, and welfare of pigs. Therefore, the study objective was to determine if combining dietary synbiotics and 0.20% l-glutamine would improve pig growth performance and intestinal health following weaning and transport when compared with traditionally used dietary antibiotics. Because previous research indicates that l-glutamine improves swine growth performance and synbiotics reduce enterogenic bacteria, it was hypothesized that supplementing diets with 0.20% l-glutamine (GLN) and synbiotics (SYN; 3 strains of Lactobacillus [1.2 × 10^9 cfu/g of strain/pig/d] + ß-glucan [0.01 g/pig/d] + fructooligosaccharide [0.01 g/pig/d]) would have an additive effect and improve pig performance and intestinal health over that of dietary antibiotics. Mixed-sex pigs (N = 226; 5.86 ± 0.11 kg body weight [BW]) were weaned (19.4 ± 0.2 d of age) and transported for 12 h in central Indiana. Pigs were blocked by BW and allotted to one of two dietary treatments (5 to 6 pigs per pen): antibiotics (positive control [PC]; chlortetracycline [441 ppm] + tiamulin [38.5 ppm]), no antibiotics (negative control [NC]), GLN, SYN, or the NC diet with both the GLN and SYN additives (GLN + SYN) fed for 14 d. From day 14 post-weaning to the end of the grow-finish period, all pigs were provided common antibiotic-free diets. Data were analyzed using PROC GLIMMIX and PROC MIXED in SAS 9.4. Overall, haptoglobin was greater (P = 0.03; 216%) in NC pigs compared with PC pigs. On day 13, GLN and PC pigs tended to have reduced (P = 0.07; 75.2% and 67.3%, respectively) haptoglobin compared with NC pigs. On day 34, the jejunal goblet cell count per villi and per millimeter tended to be greater (P < 0.08; 71.4% and 62.9%, respectively) in SYN pigs compared with all other dietary treatments. Overall, jejunal mucosa tumor necrosis factor-alpha (TNFα) gene expression tended to be greater (P = 0.09; 40.0%) in NC pigs compared with PC pigs on day 34. On day 34, jejunal mucosa TNFα gene expression tended to be greater (P = 0.09; 33.3%, 41.2%, and 60.0%, respectively) in GLN pigs compared with SYN, GLN + SYN, and PC pigs. Although it was determined that some metrics of pig health were improved by the addition of GLN and SYN (i.e., haptoglobin and goblet cell count), overall, there were very few differences detected between dietary treatments and this may be related to the stress load incurred by the pigs.

Effects of mineral methionine hydroxy analog chelate in sow diets on epigenetic modification and growth of progeny.

The study was conducted to determine the effects of mineral methionine hydroxy analog chelate (MMHAC) partially replacing inorganic trace minerals in sow diets on epigenetic and transcriptional changes in the muscle and jejunum of progeny. The MMHAC is zinc (Zn), manganese (Mn), and copper (Cu) chelated with methionine hydroxy analog (Zn-, Mn-, and Cu-methionine hydroxy analog chelate [MHAC]). On day 35 of gestation, 60 pregnant sows were allotted to two dietary treatments in a randomized completed block design using parity as a block: 1) ITM: inorganic trace minerals with zinc sulfate (ZnSO4), manganese oxide (MnO), and copper sulfate (CuSO4) and 2) CTM: 50% of ITM was replaced with MMHAC (MINTREX trace minerals, Novus International Inc., St Charles, MO). Gestation and lactation diets were formulated to meet or exceed NRC requirements. On days 1 and 18 of lactation, milk samples from 16 sows per treatment were collected to measure immunoglobulins (immunoglobulin G, immunoglobulin A, and immunoglobulin M) and micromineral concentrations. Two pigs per litter were selected to collect blood to measure the concentration of immunoglobulins in the serum, and then euthanized to collect jejunal mucosa, jejunum tissues, and longissimus muscle to measure global deoxyribonucleic acid methylation, histone acetylation, cytokines, and jejunal histomorphology at birth and day 18 of lactation. Data were analyzed using Proc MIXED of SAS. Supplementation of MMHAC tended to decrease (P = 0.059) body weight (BW) loss of sows during lactation and tended to increase (P = 0.098) piglet BW on day 18 of lactation. Supplementation of MMHAC increased (P < 0.05) global histone acetylation and tended to decrease myogenic regulatory factor 4 messenger ribonucleic acid (mRNA; P = 0.068) and delta 4-desaturase sphingolipid1 (DEGS1) mRNA (P = 0.086) in longissimus muscle of piglets at birth. Supplementation of MMHAC decreased (P < 0.05) nuclear factor kappa B mRNA in the jejunum and DEGS1 mRNA in longissimus muscle and tended to decrease mucin-2 (MUC2) mRNA (P = 0.057) and transforming growth factor-beta 1 (TGF-ß1) mRNA (P = 0.057) in the jejunum of piglets on day 18 of lactation. There were, however, no changes in the amounts of tumor necrosis factor-alpha, interleukin-8, TGF-ß, MUC2, and myogenic factor 6 in the tissues by MMHAC. In conclusion, maternal supplementation of MMHAC could contribute to histone acetylation and programming in the fetus, which potentially regulates intestinal health and skeletal muscle development of piglets at birth and weaning, possibly leading to enhanced growth of their piglets.

Effects of N-carbamylglutamate on steroidogenesis and relative abundances of mRNA transcripts in pig placental trophoblasts.

Supplementation of N-carbamylglutamate (NCG) improves gestation outcomes, with increased piglet within-litter uniformity of birth weight and reduced peripheral steroid concentrations in pregnant sows and ewes. It was hypothesized that the effect of NCG on placental function results from direct effects on the placental trophoblasts. There, therefore, was investigation of the effects of NCG on pig placental trophoblast (pTr) steroidogenesis, mRNA transcript abundance, and cell proliferation in vitro. The pTr were treated with NCG in serum-free medium for 24-48 h. Treatment with NCG inhibited pTr progesterone, androstenedione, testosterone (all P <  0.01), and estradiol (P <  0.05) production, whereas it promoted (P <  0.05) pTr proliferation. Treatment with NCG suppressed (P <  0.05) the relative abundances of CYP11A1, CYP19A1, and CASP3 and increased abundances of CCDN1 (P <  0.01) and CDK4 (P <  0.05) mRNA transcripts in pTr, whereas NCG treatment had no effect (P >  0.10) on relative abundances of StAR, HSD17B4, or HSD3B mRNA transcripts. Treatments with NCG can increase pTr cell numbers of sows through upregulating CCND1 and CDK4 and suppressing CASP3 mRNA transcript abundances, while modulating steroidogenesis through effects on CYP11A1 and CYP19A1 mRNA transcript abundances. It is concluded that NCG may have a direct action on pTr and may regulate placental function by suppressing pTr differentiation as a consequence of lesser steroid synthesis while promoting pTr proliferation and inhibiting apoptosis in sows.

Evaluation of a decision support system for precision feeding of gestating sows.

Precision feeding (PF) with the daily mixing of 2 diets with different lysine content (high (H) or low (L)) was previously reported for growing pigs to reduce protein intake and N excretion compared with a conventional feeding (CF) based on a single diet (C). Using a simulation approach based on farm data, the objective of the present paper was to describe and evaluate a decision support system for the PF of gestating sows allowing the daily distribution of a tailored ration to each sow. Two datasets, 1 of 2,511 gestations (farm A) and 1 of 2,528 gestations (farm B), reporting sows' characteristics at insemination and objectives at farrowing were used as inputs for a Python model. This model, mainly based on InraPorc, calculates the nutrient requirements of each sow over gestation and simulates the impact of PF in comparison to CF. Simulated diets L, H, and C contained 3.0, 6.5, and 4.8 g/kg of standardized ileal digestible lysine (SID Lys) and 2.0, 3.3, and 2.5 g/kg of standardized total tract digestible phosphorus (STTD-P), respectively. The influence of farm, parity, gestation week, and their interactions, on calculated SID Lys and STTD-P requirements was analyzed applying a mixed model. The calculated SID Lys and STTD-P requirements increased markedly in the last third of gestation (P < 0.01) and were higher for primiparous than for multiparous sows, unless after week 14 for STTD-P requirement. The calculated SID AA and mineral requirements were lower for farm B than farm A (respectively, 2.94 vs. 3.08 g/kg for SID Lys and 1.30 vs. 1.35 g/kg for STTD-P, P < 0.01). On average, feed L represented 86% and 92% of the feed projected to be delivered by the PF strategy in farms A and B, respectively. Compared to CF, average calculated dietary SID Lys content was lowered by 27% and 32% with PF, for farms A and B, respectively, while average calculated dietary phosphorus content was lowered by 13% and 16%. The simulated proportions of sows in excess and deficient in SID Lys were reduced with PF. Compared to CF, the PF strategy allowed for a 3.6% reduction in simulated feed cost per sow during gestation, and reduced nitrogen and phosphorus intake (by 11.0% and 13.8%, respectively) and excretion (by 16.7% and 15.4%, respectively). To conclude, these simulations indicate that PF of gestating sow appears to be relevant to meet the amino acid requirement while reducing feed cost, and supplies and excretion of nitrogen and phosphorus.

Effects of dietary inulin during late gestation on sow physiology, farrowing duration and piglet performance.

In this study there was evaluation of effects of dietary inulin during late gestation on sow physiology, farrowing duration and piglet performance. At day 80 of gestation sows were randomly assigned to four groups：basal diet (CON); or basal diet with 0.8 %; 1.6 %; or 2.4 % inulin. The feeding of the diet with 1.6 % inulin resulted in larger weights of the litter at birth a shorter duration of the farrowing period, lesser average birth interval between piglets, lesser number of piglets dead at birth, and fewer piglets/sow dead at birth (P < 0.05). When sows were fed 0.8 % and 1.6 % IN, there was a larger litter weight at weaning, sow average daily feed intake and piglet average daily gain during lactation compared with values for these variables in the CON group (P <  0.05). Additionally, there was an increase in serum concentration of free fatty acid, total cholesterol, and high-density lipoprotein cholesterol with increasing amounts of inulin in the diet (linear, P <  0.05). Sows fed 1.6 % IN had greater serum concentrations of glucose than those in the CON group (P <  0.05). Furthermore, there was a linear increase in serum activity of total antioxidant capacity, total superoxide dismutase and glutathione peroxidase with increasing amounts of inulin in the diet (P <  0.05). In conclusion, results of the present study indicated feeding inulin during late gestation improved reproductive performance of sows, thus, may be a novel additive for the pig industry in improving efficiency of pork production.

Effect of dietary pyrroloquinoline quinone disodium in sows on intestinal health of the offspring.

The objective of this study was to investigate the effects of dietary pyrroloquinoline quinone disodium (PQQ·Na2) supplementation in sows during gestation and lactation on intestinal health in offspring. A total of 40 cross-bred (landrace × large white crossed with Duroc boar) multiparity gestation sows with an average parity of 4.3 were used in this study. Forty sows were allotted to 2 dietary treatments after breeding. One group was the control sows, which were fed a corn-soybean meal control diet (Con treatment, n = 20), and the other group was the treatment sows fed a control diet with 20 mg kg-1 PQQ·Na2 after breeding and through gestation and lactation (PQQ treatment, n = 20). The activities of SOD and GSH-Px were significantly (P < 0.05) increased by PQQ·Na2 supplementation, and MDA activity was decreased (P < 0.05) in the plasma of piglets. CAT, SOD and GSH-Px activities were significantly (P < 0.05) increased, and MDA activity was decreased (P < 0.05) in the small intestine of piglets. The mRNA expression levels of SOD1, CAT and MGST1 in the jejunum were increased in newborn piglets (P < 0.05), and the mRNA expression levels of HO1, SOD1, CAT, SOD2, GPX4, GPX1 and GCLC in the jejunum were increased in weaned piglets (P < 0.05). The mRNA expression of ZO-1 was increased (P < 0.05) in the jejunum of newborn piglets, and the mRNA expression of Occludin and ZO-1 was increased (P < 0.05) in the jejunum of weaned piglets. The villous height of the duodenum and jejunum of weaned piglets was increased (P < 0.05) by dietary PQQ·Na2. In weaned piglets, Bacteroidetes and Firmicutes were the most prevalent phyla in both the Con and PQQ·Na2 treatment groups, and the most prevalent genera were Alloprevotella and Bacteroides. At the phylum level, the abundance of Firmicutes was significantly increased (P < 0.05), and the abundance of Proteobacteria was significantly decreased (P < 0.05). At the genus level, the abundance of Alloprevotella was significantly increased (P < 0.05), and the abundance of Actinobacillus and Escherichia was decreased (P < 0.05). In conclusion, dietary supplementation with PQQ·Na2 in sows during gestation and lactation had positive effects on intestinal health in offspring.

Iron homeostasis disorder in piglet intestine.

Iron plays an essential role in preventing iron deficiency anemia and ensuring the healthy growth of animals. The special physiological condition of piglets is the main cause of iron deficiency. Iron metabolism in the intestine is the basis for understanding the effects of iron on the health of piglets. In order to scientifically evaluate dietary iron supplementation doses, it is necessary to recognize the effects of iron deficiency and iron overload on piglet intestinal health. Besides, iron as a cofactor is essential for the growth of microorganisms, and microorganisms compete with the host to absorb iron. Under the stress of iron deficiency and iron overload, various control schemes (such as precise nutrition, element balance, elimination of oxidation, etc.) are effective measures to eliminate adverse effects. In this review, we comprehensively review recent findings on the effects of iron deficiency and iron overload on intestinal health. This review will provide a rational design strategy to achieve a reasonable iron supplement, which will guide the use of iron in animal husbandry.

Maternal supplementation of organic selenium during gestation improves sows and offspring antioxidant capacity and inflammatory status and promotes embryo survival.

Selenium (Se) is an essential trace element in humans and sows, having a biological function mediated in part by its incorporation into selenoproteins. This study was conducted to investigate the effects of maternal 2-hydroxy-4-methylselenobutanoic acid (HMSeBA), an organic Se source, on reproductive performance, antioxidant capacity and inflammatory status of sows and their offspring. Forty-three Landrace × Yorkshire sows were randomly allocated to receive one of the following three diets during gestation: control diet (control, basal diet, n = 15), sodium selenite (Na2SeO3) supplemented diet (Na2SeO3, basal diet + Na2SeO3 at 0.3 mg Se per kg, n = 13), and HMSeBA supplemented diet (HMSeBA, basal diet + HMSeBA at 0.3 mg Se per kg, n = 15). Blood samples of sows and piglets, placentas and piglet liver samples were analyzed for selenium status, antioxidant capacity and inflammatory cytokines. Results showed that, as compared to the control group, HMSeBA supplementation increased the number of born alive piglets and plasma concentrations of total selenium and selenoprotein P in both sows and piglets. Besides, the activities of antioxidant enzymes in the blood of sows, umbilical cord and piglets, placentas and piglets' liver were increased by dietary HMSeBA supplementation as compared to the control group, while malondialdehyde concentration (p < 0.05) was decreased in the blood of sows, umbilical cord and newborn piglets. In addition, maternal HMSeBA intake during gestation up-regulated antioxidant-related selenoprotein gene expression in the placenta (GPx2, GPx3, p < 0.05) and in the liver of newborn piglets (GPx1, GPx2, GPx3, TXNRD2, p < 0.05). Moreover, as compared to the control group, sows and newborn piglets in the Na2SeO3 and HMSeBA groups had a lower serum interleukin-6 (p < 0.05) concentration, and placentas in the HMSeBA group had lower IL-1ß, IL-6 and IL-8 gene expression (p < 0.05). In conclusion, maternal supplementation of HMSeBA during pregnancy improved antioxidant capacities and reduced the inflammation level in mater, placenta, and fetus. This finding may highlight the important role of selenoproteins (especially GPXs) in preventing negative consequences of over-production of free radicals and inflammatory cytokines during gestation and at births.

Dietary guanidinoacetic acid supplementation improved carcass characteristics, meat quality and muscle fibre traits in growing-finishing gilts.

This study was designed to evaluate the effects of guanidinoacetic acid (GAA) on growth performance, carcass characteristics, meat and muscle fibre traits of growing-finishing gilts. 300 female PIC pigs were randomly divided (30.10 ± 2.94 kg) into 2 treatments with 6 replicates of 25 each for a 100-day trial. Two dietary treatments were comprised of a control diet and a control diet fortified with 450 mg/kg GAA. Growth performance was evaluated for each phase. Carcass characteristics and meat quality were determined at last phase. Gilts had free access to feed and water during the experiment. The result indicated that GAA did not affect growth performance (p > 0.05). GAA not only increased longissimus dorsi (LM) muscle weight but also decreased its shear force, b*value and drip loss (p < 0.05). Mandibular fat index was decreased by GAA (p < 0.05). GAA upregulated myosin heavy chain (MyHC) I mRNA expression with lower myofibre cross-sectional area and fibre diameter in LM muscle (p < .05). In conclusion, GAA can improve carcass characteristics and meat quality by changing muscle fibre characteristics and reducing mandibular fat index in finishing gilts.